Mercurial > hg > graal-compiler
diff src/share/vm/c1/c1_Canonicalizer.cpp @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
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date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | 3cf667df43ef |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/c1/c1_Canonicalizer.cpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,877 @@ +/* + * Copyright 1999-2006 Sun Microsystems, Inc. All Rights Reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +#include "incls/_precompiled.incl" +#include "incls/_c1_Canonicalizer.cpp.incl" + + +static void do_print_value(Value* vp) { + (*vp)->print_line(); +} + +void Canonicalizer::set_canonical(Value x) { + assert(x != NULL, "value must exist"); + // Note: we can not currently substitute root nodes which show up in + // the instruction stream (because the instruction list is embedded + // in the instructions). + if (canonical() != x) { + if (PrintCanonicalization) { + canonical()->input_values_do(do_print_value); + canonical()->print_line(); + tty->print_cr("canonicalized to:"); + x->input_values_do(do_print_value); + x->print_line(); + tty->cr(); + } + assert(_canonical->type()->tag() == x->type()->tag(), "types must match"); + _canonical = x; + } +} + + +void Canonicalizer::move_const_to_right(Op2* x) { + if (x->x()->type()->is_constant() && x->is_commutative()) x->swap_operands(); +} + + +void Canonicalizer::do_Op2(Op2* x) { + if (x->x() == x->y()) { + switch (x->op()) { + case Bytecodes::_isub: set_constant(0); return; + case Bytecodes::_lsub: set_constant(jlong_cast(0)); return; + case Bytecodes::_iand: // fall through + case Bytecodes::_land: // fall through + case Bytecodes::_ior: // fall through + case Bytecodes::_lor : set_canonical(x->x()); return; + case Bytecodes::_ixor: set_constant(0); return; + case Bytecodes::_lxor: set_constant(jlong_cast(0)); return; + } + } + + if (x->x()->type()->is_constant() && x->y()->type()->is_constant()) { + // do constant folding for selected operations + switch (x->type()->tag()) { + case intTag: + { jint a = x->x()->type()->as_IntConstant()->value(); + jint b = x->y()->type()->as_IntConstant()->value(); + switch (x->op()) { + case Bytecodes::_iadd: set_constant(a + b); return; + case Bytecodes::_isub: set_constant(a - b); return; + case Bytecodes::_imul: set_constant(a * b); return; + case Bytecodes::_idiv: + if (b != 0) { + if (a == min_jint && b == -1) { + set_constant(min_jint); + } else { + set_constant(a / b); + } + return; + } + break; + case Bytecodes::_irem: + if (b != 0) { + if (a == min_jint && b == -1) { + set_constant(0); + } else { + set_constant(a % b); + } + return; + } + break; + case Bytecodes::_iand: set_constant(a & b); return; + case Bytecodes::_ior : set_constant(a | b); return; + case Bytecodes::_ixor: set_constant(a ^ b); return; + } + } + break; + case longTag: + { jlong a = x->x()->type()->as_LongConstant()->value(); + jlong b = x->y()->type()->as_LongConstant()->value(); + switch (x->op()) { + case Bytecodes::_ladd: set_constant(a + b); return; + case Bytecodes::_lsub: set_constant(a - b); return; + case Bytecodes::_lmul: set_constant(a * b); return; + case Bytecodes::_ldiv: + if (b != 0) { + set_constant(SharedRuntime::ldiv(b, a)); + return; + } + break; + case Bytecodes::_lrem: + if (b != 0) { + set_constant(SharedRuntime::lrem(b, a)); + return; + } + break; + case Bytecodes::_land: set_constant(a & b); return; + case Bytecodes::_lor : set_constant(a | b); return; + case Bytecodes::_lxor: set_constant(a ^ b); return; + } + } + break; + // other cases not implemented (must be extremely careful with floats & doubles!) + } + } + // make sure constant is on the right side, if any + move_const_to_right(x); + + if (x->y()->type()->is_constant()) { + // do constant folding for selected operations + switch (x->type()->tag()) { + case intTag: + if (x->y()->type()->as_IntConstant()->value() == 0) { + switch (x->op()) { + case Bytecodes::_iadd: set_canonical(x->x()); return; + case Bytecodes::_isub: set_canonical(x->x()); return; + case Bytecodes::_imul: set_constant(0); return; + // Note: for div and rem, make sure that C semantics + // corresponds to Java semantics! + case Bytecodes::_iand: set_constant(0); return; + case Bytecodes::_ior : set_canonical(x->x()); return; + } + } + break; + case longTag: + if (x->y()->type()->as_LongConstant()->value() == (jlong)0) { + switch (x->op()) { + case Bytecodes::_ladd: set_canonical(x->x()); return; + case Bytecodes::_lsub: set_canonical(x->x()); return; + case Bytecodes::_lmul: set_constant((jlong)0); return; + // Note: for div and rem, make sure that C semantics + // corresponds to Java semantics! + case Bytecodes::_land: set_constant((jlong)0); return; + case Bytecodes::_lor : set_canonical(x->x()); return; + } + } + break; + } + } +} + + +void Canonicalizer::do_Phi (Phi* x) {} +void Canonicalizer::do_Constant (Constant* x) {} +void Canonicalizer::do_Local (Local* x) {} +void Canonicalizer::do_LoadField (LoadField* x) {} + +// checks if v is in the block that is currently processed by +// GraphBuilder. This is the only block that has not BlockEnd yet. +static bool in_current_block(Value v) { + int max_distance = 4; + while (max_distance > 0 && v != NULL && v->as_BlockEnd() == NULL) { + v = v->next(); + max_distance--; + } + return v == NULL; +} + +void Canonicalizer::do_StoreField (StoreField* x) { + // If a value is going to be stored into a field or array some of + // the conversions emitted by javac are unneeded because the fields + // are packed to their natural size. + Convert* conv = x->value()->as_Convert(); + if (conv) { + Value value = NULL; + BasicType type = x->field()->type()->basic_type(); + switch (conv->op()) { + case Bytecodes::_i2b: if (type == T_BYTE) value = conv->value(); break; + case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) value = conv->value(); break; + case Bytecodes::_i2c: if (type == T_CHAR || type == T_BYTE) value = conv->value(); break; + } + // limit this optimization to current block + if (value != NULL && in_current_block(conv)) { + set_canonical(new StoreField(x->obj(), x->offset(), x->field(), value, x->is_static(), + x->lock_stack(), x->state_before(), x->is_loaded(), x->is_initialized())); + return; + } + } + +} + +void Canonicalizer::do_ArrayLength (ArrayLength* x) { + NewArray* array = x->array()->as_NewArray(); + if (array != NULL && array->length() != NULL) { + Constant* length = array->length()->as_Constant(); + if (length != NULL) { + // do not use the Constant itself, but create a new Constant + // with same value Otherwise a Constant is live over multiple + // blocks without being registered in a state array. + assert(length->type()->as_IntConstant() != NULL, "array length must be integer"); + set_constant(length->type()->as_IntConstant()->value()); + } + } else { + LoadField* lf = x->array()->as_LoadField(); + if (lf != NULL && lf->field()->is_constant()) { + ciObject* c = lf->field()->constant_value().as_object(); + if (c->is_array()) { + ciArray* array = (ciArray*) c; + set_constant(array->length()); + } + } + } +} + +void Canonicalizer::do_LoadIndexed (LoadIndexed* x) {} +void Canonicalizer::do_StoreIndexed (StoreIndexed* x) { + // If a value is going to be stored into a field or array some of + // the conversions emitted by javac are unneeded because the fields + // are packed to their natural size. + Convert* conv = x->value()->as_Convert(); + if (conv) { + Value value = NULL; + BasicType type = x->elt_type(); + switch (conv->op()) { + case Bytecodes::_i2b: if (type == T_BYTE) value = conv->value(); break; + case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) value = conv->value(); break; + case Bytecodes::_i2c: if (type == T_CHAR || type == T_BYTE) value = conv->value(); break; + } + // limit this optimization to current block + if (value != NULL && in_current_block(conv)) { + set_canonical(new StoreIndexed(x->array(), x->index(), x->length(), + x->elt_type(), value, x->lock_stack())); + return; + } + } + + +} + + +void Canonicalizer::do_NegateOp(NegateOp* x) { + ValueType* t = x->x()->type(); + if (t->is_constant()) { + switch (t->tag()) { + case intTag : set_constant(-t->as_IntConstant ()->value()); return; + case longTag : set_constant(-t->as_LongConstant ()->value()); return; + case floatTag : set_constant(-t->as_FloatConstant ()->value()); return; + case doubleTag: set_constant(-t->as_DoubleConstant()->value()); return; + default : ShouldNotReachHere(); + } + } +} + + +void Canonicalizer::do_ArithmeticOp (ArithmeticOp* x) { do_Op2(x); } + + +void Canonicalizer::do_ShiftOp (ShiftOp* x) { + ValueType* t = x->x()->type(); + ValueType* t2 = x->y()->type(); + if (t->is_constant()) { + switch (t->tag()) { + case intTag : if (t->as_IntConstant()->value() == 0) { set_constant(0); return; } break; + case longTag : if (t->as_LongConstant()->value() == (jlong)0) { set_constant(jlong_cast(0)); return; } break; + default : ShouldNotReachHere(); + } + if (t2->is_constant()) { + if (t->tag() == intTag) { + int value = t->as_IntConstant()->value(); + int shift = t2->as_IntConstant()->value() & 31; + jint mask = ~(~0 << (32 - shift)); + if (shift == 0) mask = ~0; + switch (x->op()) { + case Bytecodes::_ishl: set_constant(value << shift); return; + case Bytecodes::_ishr: set_constant(value >> shift); return; + case Bytecodes::_iushr: set_constant((value >> shift) & mask); return; + } + } else if (t->tag() == longTag) { + jlong value = t->as_LongConstant()->value(); + int shift = t2->as_IntConstant()->value() & 63; + jlong mask = ~(~jlong_cast(0) << (64 - shift)); + if (shift == 0) mask = ~jlong_cast(0); + switch (x->op()) { + case Bytecodes::_lshl: set_constant(value << shift); return; + case Bytecodes::_lshr: set_constant(value >> shift); return; + case Bytecodes::_lushr: set_constant((value >> shift) & mask); return; + } + } + } + } + if (t2->is_constant()) { + switch (t2->tag()) { + case intTag : if (t2->as_IntConstant()->value() == 0) set_canonical(x->x()); return; + case longTag : if (t2->as_IntConstant()->value() == 0) set_canonical(x->x()); return; + default : ShouldNotReachHere(); + } + } +} + + +void Canonicalizer::do_LogicOp (LogicOp* x) { do_Op2(x); } +void Canonicalizer::do_CompareOp (CompareOp* x) { + if (x->x() == x->y()) { + switch (x->x()->type()->tag()) { + case longTag: set_constant(0); break; + case floatTag: { + FloatConstant* fc = x->x()->type()->as_FloatConstant(); + if (fc) { + if (g_isnan(fc->value())) { + set_constant(x->op() == Bytecodes::_fcmpl ? -1 : 1); + } else { + set_constant(0); + } + } + break; + } + case doubleTag: { + DoubleConstant* dc = x->x()->type()->as_DoubleConstant(); + if (dc) { + if (g_isnan(dc->value())) { + set_constant(x->op() == Bytecodes::_dcmpl ? -1 : 1); + } else { + set_constant(0); + } + } + break; + } + } + } else if (x->x()->type()->is_constant() && x->y()->type()->is_constant()) { + switch (x->x()->type()->tag()) { + case longTag: { + jlong vx = x->x()->type()->as_LongConstant()->value(); + jlong vy = x->y()->type()->as_LongConstant()->value(); + if (vx == vy) + set_constant(0); + else if (vx < vy) + set_constant(-1); + else + set_constant(1); + break; + } + + case floatTag: { + float vx = x->x()->type()->as_FloatConstant()->value(); + float vy = x->y()->type()->as_FloatConstant()->value(); + if (g_isnan(vx) || g_isnan(vy)) + set_constant(x->op() == Bytecodes::_fcmpl ? -1 : 1); + else if (vx == vy) + set_constant(0); + else if (vx < vy) + set_constant(-1); + else + set_constant(1); + break; + } + + case doubleTag: { + double vx = x->x()->type()->as_DoubleConstant()->value(); + double vy = x->y()->type()->as_DoubleConstant()->value(); + if (g_isnan(vx) || g_isnan(vy)) + set_constant(x->op() == Bytecodes::_dcmpl ? -1 : 1); + else if (vx == vy) + set_constant(0); + else if (vx < vy) + set_constant(-1); + else + set_constant(1); + break; + } + } + + } +} + + +void Canonicalizer::do_IfInstanceOf(IfInstanceOf* x) {} + +void Canonicalizer::do_IfOp(IfOp* x) { + // Caution: do not use do_Op2(x) here for now since + // we map the condition to the op for now! + move_const_to_right(x); +} + + +void Canonicalizer::do_Intrinsic (Intrinsic* x) { + switch (x->id()) { + case vmIntrinsics::_floatToRawIntBits : { + FloatConstant* c = x->argument_at(0)->type()->as_FloatConstant(); + if (c != NULL) { + JavaValue v; + v.set_jfloat(c->value()); + set_constant(v.get_jint()); + } + break; + } + case vmIntrinsics::_intBitsToFloat : { + IntConstant* c = x->argument_at(0)->type()->as_IntConstant(); + if (c != NULL) { + JavaValue v; + v.set_jint(c->value()); + set_constant(v.get_jfloat()); + } + break; + } + case vmIntrinsics::_doubleToRawLongBits : { + DoubleConstant* c = x->argument_at(0)->type()->as_DoubleConstant(); + if (c != NULL) { + JavaValue v; + v.set_jdouble(c->value()); + set_constant(v.get_jlong()); + } + break; + } + case vmIntrinsics::_longBitsToDouble : { + LongConstant* c = x->argument_at(0)->type()->as_LongConstant(); + if (c != NULL) { + JavaValue v; + v.set_jlong(c->value()); + set_constant(v.get_jdouble()); + } + break; + } + } +} + +void Canonicalizer::do_Convert (Convert* x) { + if (x->value()->type()->is_constant()) { + switch (x->op()) { + case Bytecodes::_i2b: set_constant((int)((x->value()->type()->as_IntConstant()->value() << 24) >> 24)); break; + case Bytecodes::_i2s: set_constant((int)((x->value()->type()->as_IntConstant()->value() << 16) >> 16)); break; + case Bytecodes::_i2c: set_constant((int)(x->value()->type()->as_IntConstant()->value() & ((1<<16)-1))); break; + case Bytecodes::_i2l: set_constant((jlong)(x->value()->type()->as_IntConstant()->value())); break; + case Bytecodes::_i2f: set_constant((float)(x->value()->type()->as_IntConstant()->value())); break; + case Bytecodes::_i2d: set_constant((double)(x->value()->type()->as_IntConstant()->value())); break; + case Bytecodes::_l2i: set_constant((int)(x->value()->type()->as_LongConstant()->value())); break; + case Bytecodes::_l2f: set_constant(SharedRuntime::l2f(x->value()->type()->as_LongConstant()->value())); break; + case Bytecodes::_l2d: set_constant(SharedRuntime::l2d(x->value()->type()->as_LongConstant()->value())); break; + case Bytecodes::_f2d: set_constant((double)(x->value()->type()->as_FloatConstant()->value())); break; + case Bytecodes::_f2i: set_constant(SharedRuntime::f2i(x->value()->type()->as_FloatConstant()->value())); break; + case Bytecodes::_f2l: set_constant(SharedRuntime::f2l(x->value()->type()->as_FloatConstant()->value())); break; + case Bytecodes::_d2f: set_constant((float)(x->value()->type()->as_DoubleConstant()->value())); break; + case Bytecodes::_d2i: set_constant(SharedRuntime::d2i(x->value()->type()->as_DoubleConstant()->value())); break; + case Bytecodes::_d2l: set_constant(SharedRuntime::d2l(x->value()->type()->as_DoubleConstant()->value())); break; + default: + ShouldNotReachHere(); + } + } + + Value value = x->value(); + BasicType type = T_ILLEGAL; + LoadField* lf = value->as_LoadField(); + if (lf) { + type = lf->field_type(); + } else { + LoadIndexed* li = value->as_LoadIndexed(); + if (li) { + type = li->elt_type(); + } else { + Convert* conv = value->as_Convert(); + if (conv) { + switch (conv->op()) { + case Bytecodes::_i2b: type = T_BYTE; break; + case Bytecodes::_i2s: type = T_SHORT; break; + case Bytecodes::_i2c: type = T_CHAR; break; + } + } + } + } + if (type != T_ILLEGAL) { + switch (x->op()) { + case Bytecodes::_i2b: if (type == T_BYTE) set_canonical(x->value()); break; + case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) set_canonical(x->value()); break; + case Bytecodes::_i2c: if (type == T_CHAR) set_canonical(x->value()); break; + } + } else { + Op2* op2 = x->value()->as_Op2(); + if (op2 && op2->op() == Bytecodes::_iand && op2->y()->type()->is_constant()) { + jint safebits = 0; + jint mask = op2->y()->type()->as_IntConstant()->value(); + switch (x->op()) { + case Bytecodes::_i2b: safebits = 0x7f; break; + case Bytecodes::_i2s: safebits = 0x7fff; break; + case Bytecodes::_i2c: safebits = 0xffff; break; + } + // When casting a masked integer to a smaller signed type, if + // the mask doesn't include the sign bit the cast isn't needed. + if (safebits && (mask & ~safebits) == 0) { + set_canonical(x->value()); + } + } + } + +} + +void Canonicalizer::do_NullCheck (NullCheck* x) { + if (x->obj()->as_NewArray() != NULL || x->obj()->as_NewInstance() != NULL) { + set_canonical(x->obj()); + } else { + Constant* con = x->obj()->as_Constant(); + if (con) { + ObjectType* c = con->type()->as_ObjectType(); + if (c && c->is_loaded()) { + ObjectConstant* oc = c->as_ObjectConstant(); + if (!oc || !oc->value()->is_null_object()) { + set_canonical(con); + } + } + } + } +} + +void Canonicalizer::do_Invoke (Invoke* x) {} +void Canonicalizer::do_NewInstance (NewInstance* x) {} +void Canonicalizer::do_NewTypeArray (NewTypeArray* x) {} +void Canonicalizer::do_NewObjectArray (NewObjectArray* x) {} +void Canonicalizer::do_NewMultiArray (NewMultiArray* x) {} +void Canonicalizer::do_CheckCast (CheckCast* x) { + if (x->klass()->is_loaded()) { + Value obj = x->obj(); + ciType* klass = obj->exact_type(); + if (klass == NULL) klass = obj->declared_type(); + if (klass != NULL && klass->is_loaded() && klass->is_subtype_of(x->klass())) { + set_canonical(obj); + return; + } + // checkcast of null returns null + if (obj->as_Constant() && obj->type()->as_ObjectType()->constant_value()->is_null_object()) { + set_canonical(obj); + } + } +} +void Canonicalizer::do_InstanceOf (InstanceOf* x) { + if (x->klass()->is_loaded()) { + Value obj = x->obj(); + ciType* exact = obj->exact_type(); + if (exact != NULL && exact->is_loaded() && (obj->as_NewInstance() || obj->as_NewArray())) { + set_constant(exact->is_subtype_of(x->klass()) ? 1 : 0); + return; + } + // instanceof null returns false + if (obj->as_Constant() && obj->type()->as_ObjectType()->constant_value()->is_null_object()) { + set_constant(0); + } + } + +} +void Canonicalizer::do_MonitorEnter (MonitorEnter* x) {} +void Canonicalizer::do_MonitorExit (MonitorExit* x) {} +void Canonicalizer::do_BlockBegin (BlockBegin* x) {} +void Canonicalizer::do_Goto (Goto* x) {} + + +static bool is_true(jlong x, If::Condition cond, jlong y) { + switch (cond) { + case If::eql: return x == y; + case If::neq: return x != y; + case If::lss: return x < y; + case If::leq: return x <= y; + case If::gtr: return x > y; + case If::geq: return x >= y; + } + ShouldNotReachHere(); + return false; +} + + +void Canonicalizer::do_If(If* x) { + // move const to right + if (x->x()->type()->is_constant()) x->swap_operands(); + // simplify + const Value l = x->x(); ValueType* lt = l->type(); + const Value r = x->y(); ValueType* rt = r->type(); + + if (l == r && !lt->is_float_kind()) { + // pattern: If (a cond a) => simplify to Goto + BlockBegin* sux; + switch (x->cond()) { + case If::eql: sux = x->sux_for(true); break; + case If::neq: sux = x->sux_for(false); break; + case If::lss: sux = x->sux_for(false); break; + case If::leq: sux = x->sux_for(true); break; + case If::gtr: sux = x->sux_for(false); break; + case If::geq: sux = x->sux_for(true); break; + } + // If is a safepoint then the debug information should come from the state_before of the If. + set_canonical(new Goto(sux, x->state_before(), x->is_safepoint())); + return; + } + + if (lt->is_constant() && rt->is_constant()) { + if (x->x()->as_Constant() != NULL) { + // pattern: If (lc cond rc) => simplify to: Goto + BlockBegin* sux = x->x()->as_Constant()->compare(x->cond(), x->y(), + x->sux_for(true), + x->sux_for(false)); + if (sux != NULL) { + // If is a safepoint then the debug information should come from the state_before of the If. + set_canonical(new Goto(sux, x->state_before(), x->is_safepoint())); + } + } + } else if (rt->as_IntConstant() != NULL) { + // pattern: If (l cond rc) => investigate further + const jint rc = rt->as_IntConstant()->value(); + if (l->as_CompareOp() != NULL) { + // pattern: If ((a cmp b) cond rc) => simplify to: If (x cond y) or: Goto + CompareOp* cmp = l->as_CompareOp(); + bool unordered_is_less = cmp->op() == Bytecodes::_fcmpl || cmp->op() == Bytecodes::_dcmpl; + BlockBegin* lss_sux = x->sux_for(is_true(-1, x->cond(), rc)); // successor for a < b + BlockBegin* eql_sux = x->sux_for(is_true( 0, x->cond(), rc)); // successor for a = b + BlockBegin* gtr_sux = x->sux_for(is_true(+1, x->cond(), rc)); // successor for a > b + BlockBegin* nan_sux = unordered_is_less ? lss_sux : gtr_sux ; // successor for unordered + // Note: At this point all successors (lss_sux, eql_sux, gtr_sux, nan_sux) are + // equal to x->tsux() or x->fsux(). Furthermore, nan_sux equals either + // lss_sux or gtr_sux. + if (lss_sux == eql_sux && eql_sux == gtr_sux) { + // all successors identical => simplify to: Goto + set_canonical(new Goto(lss_sux, x->state_before(), x->is_safepoint())); + } else { + // two successors differ and two successors are the same => simplify to: If (x cmp y) + // determine new condition & successors + If::Condition cond; + BlockBegin* tsux = NULL; + BlockBegin* fsux = NULL; + if (lss_sux == eql_sux) { cond = If::leq; tsux = lss_sux; fsux = gtr_sux; } + else if (lss_sux == gtr_sux) { cond = If::neq; tsux = lss_sux; fsux = eql_sux; } + else if (eql_sux == gtr_sux) { cond = If::geq; tsux = eql_sux; fsux = lss_sux; } + else { ShouldNotReachHere(); } + If* canon = new If(cmp->x(), cond, nan_sux == tsux, cmp->y(), tsux, fsux, cmp->state_before(), x->is_safepoint()); + if (cmp->x() == cmp->y()) { + do_If(canon); + } else { + set_canonical(canon); + set_bci(cmp->bci()); + } + } + } else if (l->as_InstanceOf() != NULL) { + // NOTE: Code permanently disabled for now since it leaves the old InstanceOf + // instruction in the graph (it is pinned). Need to fix this at some point. + return; + // pattern: If ((obj instanceof klass) cond rc) => simplify to: IfInstanceOf or: Goto + InstanceOf* inst = l->as_InstanceOf(); + BlockBegin* is_inst_sux = x->sux_for(is_true(1, x->cond(), rc)); // successor for instanceof == 1 + BlockBegin* no_inst_sux = x->sux_for(is_true(0, x->cond(), rc)); // successor for instanceof == 0 + if (is_inst_sux == no_inst_sux && inst->is_loaded()) { + // both successors identical and klass is loaded => simplify to: Goto + set_canonical(new Goto(is_inst_sux, x->state_before(), x->is_safepoint())); + } else { + // successors differ => simplify to: IfInstanceOf + set_canonical(new IfInstanceOf(inst->klass(), inst->obj(), true, inst->bci(), is_inst_sux, no_inst_sux)); + } + } + } else if (rt == objectNull && (l->as_NewInstance() || l->as_NewArray())) { + if (x->cond() == Instruction::eql) { + set_canonical(new Goto(x->fsux(), x->state_before(), x->is_safepoint())); + } else { + assert(x->cond() == Instruction::neq, "only other valid case"); + set_canonical(new Goto(x->tsux(), x->state_before(), x->is_safepoint())); + } + } +} + + +void Canonicalizer::do_TableSwitch(TableSwitch* x) { + if (x->tag()->type()->is_constant()) { + int v = x->tag()->type()->as_IntConstant()->value(); + BlockBegin* sux = x->default_sux(); + if (v >= x->lo_key() && v <= x->hi_key()) { + sux = x->sux_at(v - x->lo_key()); + } + set_canonical(new Goto(sux, x->state_before(), x->is_safepoint())); + } else if (x->number_of_sux() == 1) { + // NOTE: Code permanently disabled for now since the switch statement's + // tag expression may produce side-effects in which case it must + // be executed. + return; + // simplify to Goto + set_canonical(new Goto(x->default_sux(), x->state_before(), x->is_safepoint())); + } else if (x->number_of_sux() == 2) { + // NOTE: Code permanently disabled for now since it produces two new nodes + // (Constant & If) and the Canonicalizer cannot return them correctly + // yet. For now we copied the corresponding code directly into the + // GraphBuilder (i.e., we should never reach here). + return; + // simplify to If + assert(x->lo_key() == x->hi_key(), "keys must be the same"); + Constant* key = new Constant(new IntConstant(x->lo_key())); + set_canonical(new If(x->tag(), If::eql, true, key, x->sux_at(0), x->default_sux(), x->state_before(), x->is_safepoint())); + } +} + + +void Canonicalizer::do_LookupSwitch(LookupSwitch* x) { + if (x->tag()->type()->is_constant()) { + int v = x->tag()->type()->as_IntConstant()->value(); + BlockBegin* sux = x->default_sux(); + for (int i = 0; i < x->length(); i++) { + if (v == x->key_at(i)) { + sux = x->sux_at(i); + } + } + set_canonical(new Goto(sux, x->state_before(), x->is_safepoint())); + } else if (x->number_of_sux() == 1) { + // NOTE: Code permanently disabled for now since the switch statement's + // tag expression may produce side-effects in which case it must + // be executed. + return; + // simplify to Goto + set_canonical(new Goto(x->default_sux(), x->state_before(), x->is_safepoint())); + } else if (x->number_of_sux() == 2) { + // NOTE: Code permanently disabled for now since it produces two new nodes + // (Constant & If) and the Canonicalizer cannot return them correctly + // yet. For now we copied the corresponding code directly into the + // GraphBuilder (i.e., we should never reach here). + return; + // simplify to If + assert(x->length() == 1, "length must be the same"); + Constant* key = new Constant(new IntConstant(x->key_at(0))); + set_canonical(new If(x->tag(), If::eql, true, key, x->sux_at(0), x->default_sux(), x->state_before(), x->is_safepoint())); + } +} + + +void Canonicalizer::do_Return (Return* x) {} +void Canonicalizer::do_Throw (Throw* x) {} +void Canonicalizer::do_Base (Base* x) {} +void Canonicalizer::do_OsrEntry (OsrEntry* x) {} +void Canonicalizer::do_ExceptionObject(ExceptionObject* x) {} + +static bool match_index_and_scale(Instruction* instr, + Instruction** index, + int* log2_scale, + Instruction** instr_to_unpin) { + *instr_to_unpin = NULL; + + // Skip conversion ops + Convert* convert = instr->as_Convert(); + if (convert != NULL) { + instr = convert->value(); + } + + ShiftOp* shift = instr->as_ShiftOp(); + if (shift != NULL) { + if (shift->is_pinned()) { + *instr_to_unpin = shift; + } + // Constant shift value? + Constant* con = shift->y()->as_Constant(); + if (con == NULL) return false; + // Well-known type and value? + IntConstant* val = con->type()->as_IntConstant(); + if (val == NULL) return false; + if (shift->x()->type() != intType) return false; + *index = shift->x(); + int tmp_scale = val->value(); + if (tmp_scale >= 0 && tmp_scale < 4) { + *log2_scale = tmp_scale; + return true; + } else { + return false; + } + } + + ArithmeticOp* arith = instr->as_ArithmeticOp(); + if (arith != NULL) { + if (arith->is_pinned()) { + *instr_to_unpin = arith; + } + // Check for integer multiply + if (arith->op() == Bytecodes::_imul) { + // See if either arg is a known constant + Constant* con = arith->x()->as_Constant(); + if (con != NULL) { + *index = arith->y(); + } else { + con = arith->y()->as_Constant(); + if (con == NULL) return false; + *index = arith->x(); + } + if ((*index)->type() != intType) return false; + // Well-known type and value? + IntConstant* val = con->type()->as_IntConstant(); + if (val == NULL) return false; + switch (val->value()) { + case 1: *log2_scale = 0; return true; + case 2: *log2_scale = 1; return true; + case 4: *log2_scale = 2; return true; + case 8: *log2_scale = 3; return true; + default: return false; + } + } + } + + // Unknown instruction sequence; don't touch it + return false; +} + + +static bool match(UnsafeRawOp* x, + Instruction** base, + Instruction** index, + int* log2_scale) { + Instruction* instr_to_unpin = NULL; + ArithmeticOp* root = x->base()->as_ArithmeticOp(); + if (root == NULL) return false; + // Limit ourselves to addition for now + if (root->op() != Bytecodes::_ladd) return false; + // Try to find shift or scale op + if (match_index_and_scale(root->y(), index, log2_scale, &instr_to_unpin)) { + *base = root->x(); + } else if (match_index_and_scale(root->x(), index, log2_scale, &instr_to_unpin)) { + *base = root->y(); + } else if (root->y()->as_Convert() != NULL) { + Convert* convert = root->y()->as_Convert(); + if (convert->op() == Bytecodes::_i2l && convert->value()->type() == intType) { + // pick base and index, setting scale at 1 + *base = root->x(); + *index = convert->value(); + *log2_scale = 0; + } else { + return false; + } + } else { + // doesn't match any expected sequences + return false; + } + + // If the value is pinned then it will be always be computed so + // there's no profit to reshaping the expression. + return !root->is_pinned(); +} + + +void Canonicalizer::do_UnsafeRawOp(UnsafeRawOp* x) { + Instruction* base = NULL; + Instruction* index = NULL; + int log2_scale; + + if (match(x, &base, &index, &log2_scale)) { + x->set_base(base); + x->set_index(index); + x->set_log2_scale(log2_scale); + if (PrintUnsafeOptimization) { + tty->print_cr("Canonicalizer: UnsafeRawOp id %d: base = id %d, index = id %d, log2_scale = %d", + x->id(), x->base()->id(), x->index()->id(), x->log2_scale()); + } + } +} + +void Canonicalizer::do_RoundFP(RoundFP* x) {} +void Canonicalizer::do_UnsafeGetRaw(UnsafeGetRaw* x) { if (OptimizeUnsafes) do_UnsafeRawOp(x); } +void Canonicalizer::do_UnsafePutRaw(UnsafePutRaw* x) { if (OptimizeUnsafes) do_UnsafeRawOp(x); } +void Canonicalizer::do_UnsafeGetObject(UnsafeGetObject* x) {} +void Canonicalizer::do_UnsafePutObject(UnsafePutObject* x) {} +void Canonicalizer::do_UnsafePrefetchRead (UnsafePrefetchRead* x) {} +void Canonicalizer::do_UnsafePrefetchWrite(UnsafePrefetchWrite* x) {} +void Canonicalizer::do_ProfileCall(ProfileCall* x) {} +void Canonicalizer::do_ProfileCounter(ProfileCounter* x) {}